WA 6x9 folder in my pocket

Steve
Even though the 65sa is small, the 47sa is even smaller, and although olympus lenses are also small, there is about 2mm all round between the back element cluster and the helical inner. I did have doubts as to whether this would be a problem. I used 50mm 1.8 standard lenses, and if yours is anything like mine it needs the slot moving internally so it can be light tight. Incidentally to seal up the old slot in the helical I used some sticky back thick felt like stuff (b+q) that is supposed to prevent door handles banging against a wall or something. It is thicker than the thread is deep, so the felt lies jammed in the old slot, and takes on the profile of the thread, and is totally trustworthy even when the lens is fully extended. This was the only way I could figure out how to fill in the slot and make the helical and the old slot light tight.
I found mounting the new lens onto the helical required making new 'boards' - no probs if there are old ones kicking around.
Schneider have flange to film distances on their web site.

Richard. I have just bought an Olympus 50mm f1.8 lens on ebay for £2.75 so I will be trying the same conversion as you have done.

This lens has a faulty aperture mechanism so I'm not going to feel guilty about destroying a perfectly good lens.

I will wait until I get the lens and take it apart but if you don't mind, I may have some questions regarding the way you modified it - especially making a new slot.

My Minolta conversion needs an external pin and slider bracket assembly to prevent it from turning so your Olympus method would look neater.



Steve.

Steve
I must admit making a new slot and the slider were the hardest parts especially as the slider with the lens cant be used. I had a 2 inch square of alluminium about 2mm thick that I knew to be dead square all round, and I cut 2 triangular pieces off 2 of the square corners. I forget the size, but they are about 3/4 inch high, 1/2 inch at the base, and the point at the top flattened off. These triangles happily sit on a machined ledge within the bore, and if memory serves me well, I put them in place inside, opposite where the lens slider is. What I suggest is you do a lot of staring at the components! (I did loads) because I found I had to completely ditch any metal on the moving helical that wasnt going to be used, because I reversed it, to give a square 'platform' to mount a lens panel onto. Also having 4 or 5 (cant remember) starts on the thread wont help either.
As for securing these triangles in the bore I used good old epoxy, and because I was essentially fastening something flat to a round, it meant epoxy could go round the back, and both triangles could be well and trully stuck in place. As a guide to the distance apart these triangles are, I decided to copy the olympus gap. If they are square and placed well they should end up giving a very decent slot for a slider, and for the slider I cut up some brass (off a picture frame plate) that was about 1.5mm thick, bent it to 90 degrees and filed away till the long part had a 'neck' with a wider bottom - very much like the one from the oly lens. The hardest part was to get it to 'slot width' at the bottom, without it having any play. This little slider was screwed into the holes left by the oly slider.
I have to say working it all out nearly drove me mad, but so far both focusing mounts are behaving well, and I have real faith in epoxy, as I cant see how any screws etc could have been used. Also near the end of all this I found there is a seperate threaded part to the lens (under the rubber ring) that made getting infinity dead easy.
I think whatever lens you use you are in for some fun!

Thanks for the explanation. Hopefully the lens will turn up tomorrow then I can take it apart and play with it for a day or two (and stare at it a lot!) before deciding what to do.

Was a square platform mounting area the only reason for reversing the helical?

If I kept the helical the correct way round and machined a flat surface to mount a lens board/disc to, would the existing slide still work or would it be in the way of the rear elements?

I know I could wait and answer these questions myself but I'm impatient!


Steve.

I think you will find the slide is on the outside of the assembly, and as the slot runs through to the inside, it is open to the light so to speak. I pondered for ages trying to work out how to keep the slider as is, but realised it couldnt be made light tight, so inside it went, with the old slot being filled in with the felty stuff (its good) Also this move meant I could reverse the helical because the back had a better area to mount a lens plate onto, and it makes no difference. Its only the inner moving part that is reversed, the lens outer parts are the right way round because they offer 3 screw holes to fasten the whole thing onto the camera. I maybe cant make this too clear! (its hard with words and no pics) but the only part I chopped up was the inner moving helical, and as you will see apart from a few gaps to fill and make light tight the outer part with the focus ring needs little work apart from the new slot thingy. I'd be interested if you come up with a different solution to what is a pain in the arse to figure out!
I think you will run into similar problems as I had, with the slot/light tight issue, and the only way I could work round this was to put the slot in the dark, inside, with a reversed inner moving helical, and as I said it all works a treat.
Steve, the only thing in doubt here is wether your 65sa will fit the 'hole', as I mentioned the 47sa is smaller, and the 65 angulon posed no probs at all. If you have access to some metal removing machinery you may be in a good position. I only have a Dremmel.

Thanks again.

Unfortunately, it didn't turn up today so I can't spend the evening fiddling with it!

Light tightness isn't something I had thought about until you mentioned it. I'm fairly certain my Minolta lens mod doesn't have any gaps but I will have a look.

I have access to some serious metal removing equipment... possible a bit too heavy duty for this. I have a friend with a military history museum who collects and rennovates military tanks. He has a lathe which is just about small enough.

I do have a smaller lathe myself but it has been ignored for too long in my shed and has seized up (a project for another day).

I will certainly give it a go. If my lens doesn't fit then I will find something else to go in it.


Steve.

I have just found this: http://fotographis.com/4x5.htm

This uses a 50mm Nikkor lens as the focus mount. I have sent an e-mail asking for some more details but I think a Nikkor lens might be an expensive option unless I can find a broken one.

Steve.

That looks nice. Nikon lenses are bigger than Olympus, so one of those may do. I bet there was still a lot of hacking and filling to do. I only chose the oly lens because I had one here, ready to hack up.

richard littlewood said:

Steve, the only thing in doubt here is wether your 65sa will fit the 'hole', as I mentioned the 47sa is smaller, and the 65 angulon posed no probs at all. If you have access to some metal removing machinery you may be in a good position. I only have a Dremmel.

Click to expand...

Well, my lens showed up today and was in pieces minutes after I got through the door. I'm fairly certain I can do it without reversing the helical though I can see why you reversed it with only a Dremmel to help you out as it has an 'almost designed for it' platform to mount the lens on.

In my case, I am going to cut away all of the platform and machine a lens board/disc to fit on the front using the three threaded holes (how I wish I hadn't thrown those screws in the bin!)

As for the question of the Super Angulon rear fitting..... Well, the lens rear element casing is 42mm wide. The opening in the inner helical is........ 43.5 (I did a little happy dance when I measured that!)

I have attached a couple of front and back images to see if we have both started off with the same lens just for interest.

Stay tuned for some more progress tomorrow when, hopefully, I can machine the parts I need to mount the lens (which I stupidly left at work).

I apologise to the OP (Daniel) for hijacking this thread which was supposed to be about wide angle folders but a couple of people have expressed interest.

When I get a bit further (or even finished) I will post a thread of my own detailing the construction.


Steve.

Just give it a go, I am enjoying reading your progress! Daniel.

salihonba said:

Just give it a go, I am enjoying reading your progress! Daniel.

Click to expand...

In that case, read on!

I have added a lot more images and description to this page:

http://www.freewebs.com/stevesmithphoto/pano612.html



Steve.

Steve
Any issues with the slot and light-tightness?

I cant see that there will be. I will have to hold it up to a bright light when I get it all together again.

The slot is in the same place as it was when it was a proper Olympus lens so unless the bit I removed from the front shielded the light, it should be o.k.

I have removed the inner helix to take out the flat area and I'm having trouble getting it back into the threads. I will just have to keep trying. I know it came out of there so it has to go back in!

From my pictures, does it look like I have the same lens as you used?


Steve.

Thats a different lens. I used a 50/1.8

Also it looks like the slot runs from the back, and that part will be light-tight, but what about the front of the lens, and when it is drawn out - like doing a close focus, will the groove reveal itself. So far, so good!

This one was a 50mm f1.8 too. Must be a slightly different design.

Yes, the slot is just a recess on the outer side of the helical so no gaps for light to get in. I thought it might be possible for some light to get down the side of the slot when it was wound right out but it seems to be masked fully. My mounting plate will further mask it leaving just a 42.5mm dia hole for the lens to poke through (it's actually flush with this plate at infinity).

I agree. So far, so good. Except I have just noticed that the three mounting holes on the front face are not equi-distant around the diameter like I drilled them. Oh well, I'll have another go!


Steve

I have just done some measuring.

Distance from the film plane to the front of the body: 45mm.

Distance from the back of the lens (front of lens board) to front of body (at infinity): 25.5mm.

Total distance: 70.5mm.

Schneider data sheet figure for film plane to back of lens: 70.5mm !!!

I was originally going to mount the helical mount on a plate and mount the plate on the body. Now I intend to mount it directly to the body but recess it by 3mm. This will hide the hyperfocal marks on the barrel (which will be wrong) and move the lens too close to the film. To counter this I will have a shim area to bring the film plane back to the correct place which I will find by using ground glass rather than an absolute measurement.

As the film gate and spool holders come out as one unit which locates on pins, it just needs a suitably sized spacer to butt up against to ensure the film distance is always correct.

Next week I will bite the bullet and start cutting the oak to make the body. I only have just enough for the body so I expect I will make a grey PVC body first or possibly one from 3/8" MDF.


Steve.

Some more:

Steve
Check out the other complex(?) screw mechanism in the outer part by getting under the rubber focusing ring. Its possible to move the helical lens part in and out without it turning the helical. I found this dead useful with fine adjusting for infinity while keeping the infinity point on the lens in the same place.